docs: def subreporter(self, subpath, entry):
          """
          create a reporter for a sub-report, with updated breadcrumbs and
          the same output formats
          """
  
          newbase = join(self.basedir, subpath)
          r = Reporter(newbase, entry, self.options)
  
          crumbs = list(self.breadcrumbs)
          crumbs.append((self.basedir, self.entry))
          r.breadcrumbs = crumbs
  
          r.formats = set(self.formats)
          return r